lfts

Question 1

why order LFTs

Answer 1

confirm clinical suspicioun of potential liver injury or disease or to distinguish between hepatocellular injury (hepatic jaundice) and cholestasis (post hepatic or obstructive jaundice

Question 2

what tests are used to assess liver function

Answer 2

ALT, AST, LP, GGT, bilirubin, albumin and prothrombin time

Question 3

what tests distinguish between hepatocellular damage and cholestasis

Answer 3

ALT, AST, ALP, GGT

Question 4

What are bilirubin, albumin and PT used to assess

Answer 4

the livers synthetic function

Question 5

more than a 10 fold increase in ALT

Answer 5

two arrows

Question 6

two arrows for ALP

Answer 6

more than a 3 fold increase

Question 7

when is ALT found

Answer 7

within hepatocytes and enters the blood following hepatocellular injury

Question 8

when is ALP found

Answer 8

in the liver, bile duct and bone tissues - often raised in liver pathology due to increased synthesis in response to cholestasis as a result

Question 9

what suggests hepatocellular injury

Answer 9

a greater than 10 fold increase in ALT and less than 3 fold increase in ALP

Question 10

what suggests cholestasis

Answer 10

a less than 10 fold increase in ALT and more than 3 fold increase in ALP

Question 11

what is GGT raised suggestive of

Answer 11

biliary epithelial damage and bile flow obstruction

Question 12

raised ALP and GGT

Answer 12

cholestasis

Question 13

lone ALP rise

Answer 13

non hepatobiliary pathology

Question 14

causes of isolated rise in ALP

Answer 14

bony metastases or primary bone tumours, vitamin D defiency, recent bone fractures, renal osteodystrophy

Question 15

causes of isolated bilirubin rise

Answer 15

gilberts syndrome, haemolysis

Question 16

how to check the livers synthetic functions

Answer 16

serum bilirubin, serum albumin, prothrombin time, serum blood glucose

Question 17

normal urine and normal stools

Answer 17

pre hepatic cause

Question 18

dark urine and normal stools

Answer 18

hepatic cause

Question 19

dark urine and pale stools

Answer 19

post hepatic cause (obstructive)

Question 20

causes of conjugated hyperbilirubineamia

Answer 20

hepatocellular injury and cholestasis

Question 21

causes if unconjugated hyperbiliruvineamia

Answer 21

heamolysis, impaired hepatic uptake, impaired conjugation

Question 22

what causes dark urine

Answer 22

conjugated bilirubin

Question 23

what causes pale bulky difficuly to flush stool

Answer 23

obstructive post hepatic pathology

Question 24

what does albumin do

Answer 24

helps bind water, cations, fatty acids and bilirubin and plays a role in oncotic pressure of the blood

Question 25

why can albumin fall

Answer 25

liver disease, inflammation, protein losing enteropathies or nephrotic syndrome

Question 26

what is PT

Answer 26

the measure of the bloods coagulation tendncy specificlly the extrinsic pathway. In the absence of other decondary causes such as anticoagulant drug use and vit K deficiency an increased PT can indicate liver disease and dysfinction. The liver is responsible for the syntheiss of clotting factors therefore hepatic pathology can impair this process resulting in increased prothrombin time

Question 27

ALT>AST

Answer 27

chronic liver disease

Question 28

AST>ALT

Answer 28

cirrhosis and acute alcholic hepatitis

Question 29

common causes of acute hepatocellular injury

Answer 29

poisoning, infection, liver ischaemia

Question 30

common causes of chronic hepatocellular injury

Answer 30

alcoholic fatty liver disease, non alcoholic fatty liver disease, chronic infection, primary biliary cirrhosis